sunxi: imply USB_GADGET

A good number of our boards have USB_GADGET enabled. Imply it so that all
the boards can benefit from it, and remove some boilerplate from our
defconfigs.

Reviewed-by: Ɓukasz Majewski <lukma@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index d6d9558..a7ee5fe 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -706,6 +706,7 @@
 	imply SPL_POWER_SUPPORT
 	imply SPL_SERIAL_SUPPORT
 	imply USB_FUNCTION_FASTBOOT
+	imply USB_GADGET
 
 config TARGET_TS4600
 	bool "Support TS4600"